Matrix properties
number of rows	226,340
number of columns	226,340
nonzeros	762,969
structural full rank?	yes
structural rank	226,340
# of blocks from dmperm	29,588
# strongly connected comp.	14,796
explicit zero entries	120,453
nonzero pattern symmetry	symmetric
numeric value symmetry	symmetric
type	real
structure	symmetric
Cholesky candidate?	no
positive definite?	no

author	L. Peijie
editor	J. Hogg
date	2011
kind	power network problem
2D/3D problem?	no

Additional fields	size and type
b	full 226340-by-1

Notes:

Three different kinds of optimization methods (OPF, TSCOPF, HTC)
applied to power system simulation.  All matrices are symmetric 
indefinite.  From Li Peijie, Institute of Power Systems,        
Guangxi University (beyondpeijie at gxu.edu.cn).  Collected by  
Jonathan Hogg, Rutherford Appleton Laboratory, Oxfordshire, UK. 

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	1,085,813
Cholesky flop count	5.5e+07
nnz(L+U), no partial pivoting, with AMD	1,945,286
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	26,419,220
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	71,416,606

Note that all matrix statistics (except nonzero pattern symmetry) exclude the 120453 explicit zero entries.

For a description of the statistics displayed above, click here.

Maintained by Tim Davis, last updated 12-Mar-2014.
Matrix pictures by cspy, a MATLAB function in the CSparse package.
Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.